The Best Choices for Heating Your Solar Home | And The Worst!

The largest energy consumer of any home-built in the northern hemisphere is the heating system.

Designing the correct heating system is critical in the success of the off grid home.

Build it wrong and nothing else will matter. Almost all heating systems require some form of electricity to operate whether it for the fans (oil, wood or gas hot air furnace), circulating pumps (oil, wood or gas boiler), thermostatic and safety controls (almost every system) or auger (wood pellet stove). The worst part is this extra electricity is needed most when the days are the shortest and the sunshine is scarce. Check out our favorite heating system.

Heating systems in “off the power grid” homes are often the weak link in the system. The conventional “plumbing and heating” installer will insist there is only one way of doing things and try to force you into following the building codes.

Unfortunately the building codes are often outdated, unrealistic and will not work for the solar-powered home.

First, there are a few heating options that are NOT AVAILABLE for the off grid home.

Electric Heat

Oil Furnace/Boiler

Heat Pump/Geothermal

The above heating methods are out of reach for 99% of those deciding to live off of the grid. They require far too much electricity.

Electric Heat

Using electric space heaters, baseboard heaters, boilers and/or low wattage under floor radiant heating systems consume HUGE amounts of electricity. Any heating load, whether an electric heater, a hot water heater or electric range, is too large to even consider for all but a few off the grid homes.

If you are planning on making your own electricity using solar panels, wind turbines or a gas/diesel generator it is impossible to make enough electricity to power heat loads (resistive loads). There may be times when you have enough electricity to operate a heater as in a dump load but the extra power is usually in the summer.

The one exception is the home owner fortunate enough to have a massive resource of falling water. A micro hydro powered home might be able to operate some electric heat as a dump load but it is very rare.

Oil Furnace/Boiler

Although heating oil is the primary source of heat in the above heating systems there are also some large electrical requirements as well. Oil burners use high pressure pumps to force the oil through a fine nozzle to vaporize the oil enough to burn efficiently.

They also use electricity to ignite the fuel and a fan to make a clean and aggressive flame. In addition to the boiler, there is either a large fan (furnace) or circulating pumps and zone valves (boiler) to move the heat where it is most needed.

Last but not least, is the thermostatic and safety controls which are usually operated with transformers that consume energy 24 hours per day. Anything that uses electricity 24 hours is of particular concern for the solar home. Some solar power systems are designed to sleep at night in an attempt to conserve electricity until it is required, as in the case of a light being turned on or the refrigerator compressor starting.

The thermostatic controls/safety controls will keep the system awake at night (phantom load) draining the batteries/battery bank.

Heat Pump/Geothermal

Although geothermal heating systems are very efficient by today’s standards, they are not suitable for the typical off grid home. A good heat pump system will consume about 1/3 the electricity an electric heater will use.

A small well insulated home might use 1500-2000 kWh per month just for electric heat. To heat that same home with geothermal, 500-667 kWh will need to be generated per month. If your electricity is produced with solar modules you would need to purchase another 16000-22000 watts of solar ($16,000-$22,000) and up to 52 more batteries (Trojan L16 – $15,600)) just to run the heat pump system. These numbers are based on getting 1 sun hour per day in December and January. It is just not affordable for the average homesteader. Just like electric heat, you might be able to operate a heat pump with a large water turbine. For the rest of us, we will need a less electricity dependent heating system.

UPDATE AUGUST 2015: As solar modules are getting less expensive and some homes are super insulated it is possible to heat your home with a heat pump. It will still cost a lot up front but it is possible for some.

What are the good choices for heating a solar home?

As our electricity consumption needs to be as low as possible, we will need to do things differently than our neighbors. Even something as insignificant as a circulating pump and some zone valves can use more electricity than we can spare.

The most obvious options are:

Solar Hot Water

At first it might seem like solar hot water is the obvious choice for heating your renewable energy home.

It is green, renewable and downright sexy but also very expensive, high maintenance and complicated. It is one thing to install a photovoltaic module, run some wire and connect to a charge controller. It is a whole different process for solar heating. Solar hot water collectors are often heavy, fragile and cumbersome to mount. Installing the plumbing, controls, heat exchangers, hot water storage tanks, pumps and thermostats is beyond the scope of the average homesteader. Not to say it can’t be done. It is just more than the average do-it-yourself homesteader will be ready for.

There are also major considerations such as:

How many sun hours will I get per day in the middle of winter?

How large of a storage tank will I require?

Will I need to use a double wall heat exchanger or will a single wall meet code approval?

How many collectors will I require?

How will I keep the heat transfer fluid from freezing?

Should I design a closed loop, open loo, drain-back, direct or indirect system?

What will I do if the sun doesn’t shine for a a day, a week, two weeks?

What am I going to do with the abundance of hot water I generate in the summer?

The biggest problem with a solar hot water heating system that it is required the most when it is able to produce the least.

In the middle of January, the sun rarely shines while it is one of the coldest months of the year. In the east coast of Canada we average 1 sun hour per day in late December and early January.

Undoubtedly you will need some type of ‘backup heating system for those cloudy days or very short days. Even though it is possible to design a solar hot water heating system that will work flawlessly and completely, it would be unwise to not incorporate some type of backup system. More about solar hot water to come later.

UPDATE AUGUST 2015: I have seen a few solar hot water systems that were able to provide 100% of the heat for large homes in the New England States as well as in Canada. Each of these systems cost well over $100,000 and were massive, containing up to 20 hot water collectors and storage tanks as large as 1600 gallons(6000 liters). One in particular has been operating for over ten years and the water in the storage tank (according to the owner) has never gone below 190 degrees F (88 degrees C). Pretty impressive but out of reach for me and most other homesteaders.

Wood

Burning wood is by far the most common heating method for the solar homesteader. Wood is hard work and dirty but most folks who decide to live off the grid are not deterred by a little work and dirt.

The simplest wood heating system with the lowest electricity requirement is the common wood stove. The majority of wood stoves operate with no electricity or fancy controls making them ideal for renewable energy homes. However they might not be the best choice as they only heat a small area, can be very inefficient and require the addition of firewood constantly.

Other options include the wood hot air furnace (fan uses a huge amount of electricity), indoor and outdoor wood boiler (go here for efficient circulating pump setup), pellet stove (auger and fan consume a lot of electricity) and rocket stove/rocket mass heater (impossible to get building code approval).

Propane/Natural Gas

The beauty of gas is the ease of handling and the ability to store massive amounts on your property with little effort. If you are living off the grid, you will likely use gas for cooking and/or hot water. Adding a propane/natural gas heating system is the logical next step. There is a lot of variety when looking for a gas heating system. Some are good, while some are horribly inefficient.

If you go to your local home improvement store and buy the cheapest propane heater you can get you should expect an efficiency of about 50%. For every liter of propane you purchase and consume, one half goes into home heating and the other half goes out the chimney.

You can quickly assess the efficiency of a gas heater by looking at the chimney or venting system. If the gas heater requires a steel vent or full blown chimney, you can expect it to waste a lot of propane/natural gas. If it is vented by a small plastic (ABS or PVC) vent you can be pretty sure it will be efficient. Less heat going out the vent means more heat in your home.

Propane/Natural gas heating systems can be hot water boilers(like the Polaris) , hot air furnaces (van uses a lot of power), water heaters, vented space heaters, fireplaces and non vented space heaters (most require no electricity and are 100% efficient). The efficiencies can vary widely between any of the above heaters except the non vented space heater. As it is non vented, all of the heat stays in your home making it as close to 100% efficient as possible. Check out the different propane/natural gas heating systems before making a decision.

Wood Pellet

Pellet stoves are not often talked about but they do have their place in the off grid home. They are very reliable, a lot cleaner than firewood, fairly efficient and able to be operate for long periods of time between fill ups. One of the problems with the pellet stove in the off grid home is the amount of electricity required for operation. The auger, ignition system and fan all use electricity. You must get all the details before purchasing your pellet stove. Some do not require much electricity and can operate in the event of a power outage. Some use a huge amount of electricity as their glow plug ignition system operates constantly using up to 1000 watts the whole the unit is operating.

Most wood pellet stoves take inside air for combustion of the pellets. This can be a problem as it is taking warm air from your home and dumping it outside. The air removed will be replaced with cold outside air making your home harder to heat. In a small, tight home (like an energy efficient off grid home) this can rob your home of oxygen. Fortunately you can get a pellet stove such as a Harman that uses outside air for combustion.

There is even a wood pellet stove (Harman PC45) that can burn many fuels including wheat, corn, cherry pits, sunflower seeds and others. Choosing the best wood pellet stove for your solar home can be a challenge.

Contact a reputable dealer and get a spec sheet before you make any decisions. You can even call the manufacturer to get the power requirements while the unit is operating and while it sits dormant. Some pellet stoves are a phantom load.

Now we are getting away from the traditional home heating systems.

As off grid homesteaders we always need to think outside the box. We cannot waste energy like our neighbors. It is too precious and too expensive to make our decisions lightly.

Biomass

Biomass might be an option when designing your solar/off the grid home. It is relatively new and mostly misunderstood. The term biomass heating refers to generating heat from living organisms. Most of the time the living organisms are plant based as in wood chips, compost, corn, grains etc. However some biomass energy might be gathered from animals as in the collection of methane from cows. Sounds easier than it is!

Some of the simplest biomass heating systems are nothing more than a pile of manure, leaves, sawdust and small sticks with multiple coils of pipe inside use to heat water or a pile of compost inside a green house constantly generating heat.

We are in the research and testing phase for a few types of biomass heating systems. As we get more facts and prove more concepts we will update our biomass home heating page.

Hybrid Generator Systems

The last form of heating system we will mention here is the hybrid generator heating system. Most of us will need to rely on a generator for electricity production at some point in time. Some of us have long periods without sun or very short days in the winter. A generator is just a fact of off grid life. One of the problems with a combustion engine generator is the poor efficiency. A large amount of fuel is consumed to make a small amount of electricity. In fact most of the fuel is turned into heat instead of electricity. A hybrid generator system captures that lost heat and uses it to heat your home.

The most common method of capturing the heat is by rerouting the cooling system from the radiator to a heat exchanger like the one shown above, and from the heat exchanger to your home. The other method of heat capturing is by making a heat exchanger for your exhaust pipe and directing that heat into your home. The above heat exchanger would work for exhaust as well. Some systems do both.

We have seen homes that are making up to 50% of their home heating by simply recovering the heat from the fossil fueled generator. It makes sense and is not that hard to setup.

Hi,
Thank you for commenting. While I definitely think it is possible to heat your domestic hot water with a heat pump water heater using solar, I could not really comment on heating an entire home unless I know what part of the world you are from, how large the home is, how well it is insulated and how much money you have budgeted for this project.

As I previously stated, a heat pump water heater (for domestic hot water) is a real possibility with solar being below $1 per watt. You can put the water heater in the hottest room of your home (garage or sun room if located in the warmer areas of the world) and any of the heat removed from the room to heat the water will actually cool the room giving you free air conditioning as a byproduct.

Hope this helps. If you have more info please let me know and I will do my best to answer.
Jody

Four years ago l invested $16,000.00 to go off-grid. This got me the top of the line quality equipment and by the way it is much cheaper to install what l installed 4 years ago. Panels are now half of what l paid.
The system gives us 120/240 v on a 4.4kw or 4,400 watt inverter output made by Magnum Energy, a US Company and made in america. To mount the inverter an E panel is required, usually partially or fully pre-wired for super easy hookup and a 60/80 amp charge controller which is the brains to the system. Add your panels and the batteries and your up and running. Sounds all so easy and it is if you are willing to do most of the additional work mounting your panels, run the wiring, hook-ups etc.
I purchased most of the equipment through eastern solar sites and G2 Solar out of Barrie,Ontario and Calgary Branch. Carlos is the sales manager in Calgary, great customer service. HES-PV out of Barrie is also a bunch of great guys and will do the full installation for you if you have the extra funds.
You can start small adding more panels and batteries down the road, which would made your initial costs much lower. We have no problem buying a new car/truck no problem spending $20-50,000.00 and for the price of a good used Toyota Corolla you to can be off grid with the best equipment out there..
GS

I remember when you made the decision to go off the grid. We spent many hours on the phone together. I am glad things are working out for you. It is a huge adjustment learning to live on what energy you produce but you are evidence it can be done. I have often wondered how you and Anna are doing. I fell very ill in 2010-13 and lost the solar company (renewcanada.com) and all my customers. I didn’t mean for it to happen but it did. We lost pretty much everything financially and I am still unable to work. We are still off the grid but with me being ill it has been harder for my wife to keep things going. Keep hoping for a miracle and I miss the friends I made while in business but you were one of the best. I feel like I let you down.
Gotta go to bed…Jody

Hi Everyone, We have been off-grid for 4 years now, and each year we reduce the amount of fossil fuel required due to the on going additional costs of in our case propane. Last year our hot water and stove propane costs were approx. $3-400.00 per month. Problem is we live in northern Ontario (Apsley) but my job is seasonal ($10-12,000.00). This year I installed a 40 tube HW system with two 50 gallon solar tanks thus removing any propane useage from the hot water system. We now only use propane for our stove which is super efficient in consumption thus reducing our costs huge.
When the sun is shining we run our home as a regular home, but during those off sun days which are frequent in the winter months, one must sacrifice. So the question is how far are you willing to go?
We also have three wood stoves situated so that if we run all three the whole house can be kept quite cosey, this is a one level 1000sq ft home.
Our generator is a 10k diesel Kubota which l imported from the US some years back, but what happens when propane and diesel are no longer available? Wood. You city folks will be in big trouble. Millions will die from starvation thanks to the globist bankers and Obama, you know that guy who thinks he is above it all and his minions. We are all in such trouble…..and for the truth listen to Infowars.com / AlexJones.com.
My suggestions are as follows………Backup food stuffs (6-12month supply, cook stove and wood burning stoves, DC powered fridge/freezers, well insulated home, indoor garden(winter),outdoor garden(summer,fall) and protection with atleast a .22 lever action, 3030 lever, .357/.38 lever for hunting and family protection from invaders-zoombies. I can go on and on……your choice, cash in. any paper monies and buy gold and silver……a cashless society is around the corner and all governments are buying tons of ammo,gold and silver, what does that tell you folks, good luck to all of us and don’t wait till the shit hits the fan because it will be to late. I hope l am getting my message clearly out to everyone, my mind is racing much faster then l can type……..Gary Stack

Great to hear from you. Although we haven’t focused on SHTF on SolarHomestead.com you are correct. What are we going to do when their is no diesel, propane and petrol?

We have our solar electric system large enough to operate a fridge, freezer and water pump even in the winter. We can live with out all the other electrical stuff. We now have 3 months worth of foods, meds and fuel. We have been buying silver rounds and bars for the last couple of years and have a tiny wood stove that could heat our whole house and hot water on about 3 cords per winter. We have been stocking up on Russian SKS rifles and ammo due to the reliability of the rifle and cheapness of the ammo at 18 cents a cartridge for military full metal jacket. For those who do live in the city I really am concerned. They are either going to die or relocate to the country and try to take what preppers have stored up.

Jody, 6AM this morning, my wife Anna gets me up to get the fire started, neither of us are on the midnight shift to keep the Jotul cast iron unit running 24/7 . As l threw in some smaller sticks l looked at her (the Jotul) and thought how important she is and that her and l would become best buds over the next 6 months of cold weather. Occasionally l will assist Anna as l also installed two LG Inverter V system wall units which operate in numerous AC and heating modes and draws 4.8 amps @ 240vac on full mode. After starting the 10k Kubota liquid cooled, 1800rpm diesel l cranked up the heating mode on her unit to 24C with built in thermostat, so it cycles, thus reducing the power needed to maintain its output. Our morning coffee of 10-12 cups take its share of dc amperage so thats why l engaged the diesel plus it gave us some morning battery charge. Looks like the sun will show itself today, fantastic, maybe l will be able to take a warm soak in the tub this evening. Going off grid has given me an appreciation of everything that 99.9% of the people take for grantite so when l talk about what i have installed here its not what l have, it is the fact that l took the courage to step out of my comfortable box as my sheple days have been over for along time now. Everyone seems to want solar – but very few go beyond that expression. Oh! so many folks are blinded by the truth……so l sit here and write back to you and others who read these statements and understand where l am comming from, and that’s enough. I am just listening to my morning Infowars.com – Podcast update, Amazing, We are on our own, our Governments are only concerned about their own wealth and power, but remember that we all have a choice, be your own man-master whatever or be a sheple….Ba,Ba! The great thing is we do have choice, take the blue pill or the red one.
I work here with a my boss Frank, solar applications, electrical, heating & AC, appliance repair, etc, etc. We go into cottages that are like castles, l get physically ill, HOW MUCH IS ENOUGH, and no solar backup, nothing, 0, unreal! Errogence at its best.
I can honestly say that going off-grid is the best thing l ever did. Every day has a learning curve and it’s a great feeling no matter how hard things can get. I have so much to say and l will in time. I am just very happy to help out anybody, we all need to stick together and help eachother, because when the shit really hits the fan all we will have is eachother. I gotta go, things to do, all the best everyone.
Sincerely,
Gary Stack

I hear you. It is getting ridiculous. My friends are all building bigger and bigger homes. Then when their kids grow up, they build a bigger one. We have four young children and live in a 1000 square foot home and we get by. We have four bedrooms and two bathrooms. Nothing is big but why does it have to be? Since the kids, we are using about 10 kWh per day in electricity. We heat with wood and propane and could survive just with wood for heat, cooking and hot water if we needed to. We consume about $1800 per year for propane and wood. I have friends who use three and four times that much and have no children. I don’t know how they use so much. I just know we are in trouble and don’t think we can get out of it. Keep up the great work Gary…Jody

Hi, we have used an outdoor boiler system, heating wood or wood pellets in an outdoor boiler and
heating the water which circulates into the house through pex tubing and though a converter. The air part of the furnace runs off the thermost and force heated air into the home.
I often wondered why we cant attach solar panels to the outdoor system and heat the water that way.
Are system is manufactured by Central Boiler. Could you take a look at their outdoor boiler systems and let me know if I can set my pellet stove up with solar panels?

Hi Linda,
Thank you for getting in touch. Did you mean can you produce the power your pellet stove requires with solar modules? Or are you hoping to make the hot water directly with solar modules without burning any wood or wood pellets? Just let me know and I will do my best to get your answers…Jody

Linda, You can set up any electrical devices with solar panels,charge controller and in your case a dc to ac small inverter. The dc power produced through your panels (2-3 200-300 watt rated) a 15 to 30amp charge controller which protects your batteries from being over-charged. Batteries should be a deep cycle 6-12volt rated and a small inverter 1500-3000watt rated. It all depends on the ac output amperage needed to operate the pump on your pellet stove.
The pellet stove is a great choice Linda. Find someone who can size up the hydro needed to operate the system and don’t forget to get a small backup battery charger when the sun is not out – rain,overcast conditions etc. If you size up the batteries properly your system can operat for two/three days before charging is needed……..A small price to pay to keep you warm. If you send me the specs on the pellet stove motor l can assist you with equipment needed. A 24 volt dc battery system would be the best way to go.
Four solar deep cycle 6vdc batteries, 30amp charge controller and a 2000watt dc to ac inverter plus battery cables and a small charger will run you approx. $2500.00 canadian plus installation costs, aroud $3000.00.

I think you have made an error stating 500-667 kwh per day consumption by a heat pump this kwh is a month’s consumption. If for example we assume that a 12kw geothermal heat pump with an efficiency factor of 6 then the most electricity needed is 12/6*12 hrs=24kwh per day or 720 kwh per month. Are my assumption wrong?. Thanks

Hi Dennis,
Thank you for pointing that out. You are completely correct. It should have stated 500-667 kWh per month for our particular example. It is now corrected and thank you for showing me my mistake. Take care…Jody

Yes. There are 2 ways to do it.1. Off the grid. You buy it, you make it, you store it, you use it. Pro: you’ll still have lights in a bucokalt.Con: If you don’t make enough you sit in the dark. 2. On the grid. You have the equipment to generate power that is then sold to the power co. for storage and sale. They in turn sell you power. You have 2 meters, what you generate turns backward and what you use turns forward, you hope they net to 0 at the end of the month.Pro: you don’t need to have the storage on site (batteries) and the power co. will usually give you a partial subsidy for the equipment.Con: dependent on the grid.

Can I just say what a relief to find someone who in fact knows what theyre talking about. As an off gridder I have had many struggles trying to keep my home warm in the long cold winters in Canada. My home was designed by a so called “solar expert” but he made a heating system I couldn’t possibly run on my small solar system. Thanks for the good info…

I am building an off grid home in the spring. You say electric heat is out of the question. Does that mean I can’t make any electric heat? Can I use a small space heater? What about a hair dryer? thanks…

Hi Tim, thanks for your comments. It really is out of reach for most to operate heaters from solar PV. You might be able to run a space heater but keep in mind that a heater is required when there is very little sun. We use a 1500 watt heater as a dump load (we will adding info on dump loads soon) in the spring and fall when we have extra solar power. A hair dryer is fine as they are usually only operated for 10-15 minutes instead of hours like a space heater.

I believe that you should try your hardest to get away from fossil fuels instead of recommending propane or natural gas. I do really enjoy your website, I just think fossil fuels should be avoided. Cheers

Of course. Our house is on eteclric, powered by a 5kw solar system. The AC, dryer, refrigerator, water heater is all eteclric. Our heat is from a wood stove, but we could put in a whole house eteclric heating unit if we wanted. No problem. I don’t know much about wind energy, but I know a house can be powered solely by solar power. Putting in wind power would be another expense.You would have to pay up front, when the house is bring built, but the monthly costs would be next to nothing (depending on whether you’re hooked up to your eteclric company’s grid versus on rechargeable batteries out eteclric company changes us about $6/month for the privilege to be hooked up to their system).

Hi,
I agree. I dislike fossil fuels as well but we are addicted to them. Other than wood (which is getting harder as insurance companies do not like wood heat and many cities ban them because of the smoke pollution) we do not have much else. Solar heat is out of the range of most folk’s budget unfortunately. And in areas like Canada there is very little sun when the heat is needed most. It is easy to criticize each other for our use of fossil fuels but unless we go back to the stone ages (or subsidize renewable energy technologies like we do fossil fuels) we need fossil fuels. And I repeat, I do not like fossil fuels either. That is why my home is off the power grid (our grid is fueled by the dirtiest crude you can buy) and I do everything I can to minimize our use like driving a small hybrid car as much as I can with four children. Thanks so much for your comment.Jody

Hey, we would all like to eliminate fossil fuels in our lives and be able to maintain our existance with solar applications, l hear you and so do others but, you still use fossil fuels, dirty as you have expressed but still a fossil fuel. You also mentioned your hybrid car, well, tell us about your car, don’t tell me a Toyota Prius, and if not does your vehicle use oil for engine lubrication/transmission and petro?
You have expressed to Jody how you just do not like the use of fossil fuels, and all l feel from your comments is anger, so why do l feel this?
What will you do when all fossil fuels will no longer be available, and it is not if, but when because it will happen and if you are not prepared it will be to late to make any changes.
Gary Stack

I’m not sure if you are talking to me or the person named Dilmervarteri above. I don’t think I showed anger but if I did I apologize. I am with you Gary. I believe we are heading for a world without fossil fuels eventually whether we like it or not. I am the last to judge others on their use of fossil fuels as I have only lessened my use. I still drive cars, fly on airplanes to Haiti and use some propane to heat my home and water. If I had the money I would buy a solar hot water system but I am unable at the time. I am thankful for your insight Gary. Keep it up! Jody

Rather nice post, I absolutely love this site. Keep up the great work. It is hard to find info from real world solar expert and not someone who read a book or blog and thinks they’re an expert. I will keep recommending you!!!

Thank you so much for your comment. Thank you so much for your recommendation. We are trying our best to learn to live within our means and reduce our own impact on the earth and I must say we are failing. I like to live comfortably and drive a car and even fly in an airplane to Haiti once in a awhile. I consume more fossil fuels in one flight than most people in the world use in their lifetime. We are trying to get better though and there are so many others trying as well. Thanks again…Jody

I’m impressed, I must say. Honestly rarely do I encounter a weblog that is both educative and entertaining, and let me tell you, you’ve got hit the nail on the head. Everywhere I look I see the same generic info on home heating. It is nice to find someone who has experience with the challenges of living off the grid.